<h3 class="my-3">表达式优先级顺序</h3>
<hr />
<table class="table table-bordered">
  <tr>
    <th width="20%">操作符</th>
    <th>描述</th>
   </tr>

  <tr>
    <th>\</th>
    <td>转义符</td>
    
  </tr>
  <tr>
    <th>(), (?:), (?=), [] </th>
    <td>圆括号和方括号</td>
    
  </tr>
  <tr>
    <th>*, +, ?, {{'\{n\}'}}', {{'\{n,\}'}}, {{'\{n,m\}'}}</th>
    <td>限定符</td>
    
  </tr>
  <tr>
    <th>^, $, \any</th>
    <td>位置和顺序</td>
    
  </tr>
  <tr>
    <th>|</th>
    <td>或</td>
    
  </tr>
</table>
